Navy Copter Explodes Off S.F.; 8 Are Missing

A Navy helicopter developed from a crash-plagued Marine Corps design crashed into the sea Monday while on minesweeping maneuvers off the Golden Gate, the Coast Guard said. All eight crew members were missing and presumed dead.

Witnesses reported hearing two explosions before seeing pieces of the aircraft plunge into the Pacific.

After several hours of searching the fog-shrouded crash site about 10 miles west of San Francisco, rescue helicopters and Coast Guard vessels found only seven helmets and “lots of wreckage,” Coast Guard Petty Officer Thomas Cowan said.

Cowan said the 10:45 a.m. accident was reported by a fishing boat, Northern Lights, which radioed authorities that it had heard two explosions on board the huge Navy aircraft.

Navy spokesman Bill Valente, a civilian working at the helicopter’s base at the Alameda Naval Air Station across the bay from San Francisco, said he could not confirm the report of midair explosions aboard the heavy-lift aircraft.

Navy Version of Craft

Valente did say that at the time it crashed, the MH-53E Sea Dragon--a Navy version of the troubled CH-53E Marine Corps cargo helicopter--was supposed to be pulling an electronics-packed mine-detection sled through the open sea.

“They go out on these maneuvers all the time,” he said. Another aircraft from Mine Countermeasure Squadron 15 was “in the general area” at the time of the incident, Valente added, but he did not know if the second craft was in visual or radio contact with the doomed helicopter at the time it was lost.

Valente added that Navy investigators are not sure what might have triggered an explosion. He said that besides its fuel, the aircraft normally carried no explosives other than emergency flares.

Shortly after the accident was reported, the Navy and Coast Guard each sent two rescue helicopters to the area. The Coast Guard also dispatched the cutter Blackhaw to coordinate the search and two smaller boats to assist. Cowan said the Northern Lights and several other private vessels were also helping.

Dense Fog

The search was severely hampered by dense fog, which cut visibility to 150 yards. Rescuers were also bothered by television news helicopters hovering over the sight, and the Navy asked them to clear the area.

Identities of the lost crew members were withheld pending notification of their families.

The triple-engine MH-53E Sea Dragon is identical in most of its basic mechanical systems to the Marine Corps’ CH-53E Super Stallion. Both models are produced by the Sikorsky Aircraft Division of Connecticut-based United Technologies Corp.

Jane’s “All the World’s Aircraft,” an authoritative reference book, says the Navy has ordered 32 Sea Dragons, which reportedly are deployed in three mine-sweeping squadrons.

With Monday’s accident, at least 28 servicemen have been killed in crashes of H-53E series military helicopters, although this was the first crash of the Navy’s version of the craft since the first one was delivered in June, 1986.

In addition, 68 Marines have died in crashes involving an earlier, smaller twin-engine version called the CH-53D Sea Stallion.

H-53E series craft are the largest heavy-lift, troop-carrying helicopters built outside the Soviet Union. The 16-ton aircraft--which are 99 feet long, 28 feet wide and 29 feet tall--carry up to 16 tons of cargo. Both the Sea Dragon and Super Stallion cruise at 173 m.p.h. and have a top speed of 196 m.p.h.

Last year, the Marine Corps twice grounded its worldwide fleet of 93 of the larger Super Stallions because of transmission problems. In February, 1987, the Marines began replacing “suspect” gearboxes on its craft, half of which are based at the Marine Corps Air Station in Tustin; just four months later, the second grounding was ordered because of more transmission problems.

In March, 1987, severe restrictions were placed on Super Stallions. The craft were banned from combat maneuvers and hauling heavy cargo over populated areas. When they did carry heavy cargo, passengers were restricted to four-man crews.

Emergency Procedure

At the time, the Navy said it had instructed its fliers to jettison certain loads if vibration problems were detected. By the time this emergency procedure was made public, at least two crews had been forced to use it, a Navy official said at the time.

The House Armed Services Committee has investigated the H-53E series, but committee member Robert E. Badham (R-Newport Beach) said Monday that pilot error caused most of the crashes. He said all H-53E restrictions have been lifted.

“The data thus far achieved indicates there is no inherent design flaw,” Badham said. “It (the string of crashes that prompted his investigation) was just a terribly unfortunate string of circumstances that were unrelated.”

Still, survivors of two Marines killed in CH-53E crashes have sued the craft’s manufacturer in Orange County Superior Court, alleging that defective design caused separate crashes near Twentynine Palms in May, 1986, and near the Salton Sea in January, 1987.